The study subject's primary care provider(s) will make first contact on behalf of the study so there is no appearance of a breach in confidentiality. Once a subject has expressed interest in this research study, to obtain informed consent, one of the study coordinators will explain to each subject in lay language the purpose, benefits and risks of the investigation. Consent will be given following an informative discussion period and either by reading the Informed Consent to the subject or by allowing the subject to read the consent, then reviewing it with the subject. All study coordinators have taken the Research Coordinator course and have passed their Miami CITI. Every attempt will be made to conduct this study in full compliance for the protection of the subjects. For those women who are not fluent in English and whose first language is Spanish, a Spanish version of the consent form will be used (translated by BiLingo from IRB approved English consent and submitted as an amendment to IRB). Following the subject's verbal agreement to participate in the study, the subject will sign the informed consent; the study coordinator also will sign the consent. A copy of the signed, written informed consent will be given to the study subject. The original informed consents will be placed in locked research file in study coordinators' office, 20 Ehrhardt St, #4. A copy of the informed consent also will be placed in the subject's study binder (located in locked cabinets at same location). A study coordinator note will be placed in Epic identifying an MUSC woman as participating in a vitamin D and pregnancy RCT.